RC Big Rock is a new late season variety of upland switchgrass developed from Cave-in-rock. Its distinct traits are a very tall height and high yield potential. RC Big Rock was genetically improved for upright growth habit and increased height. Its tall height provides a high quality habitat for deer. It is a late-season switchgrass with approximately 9 days later maturity than Cave-in-rock. RC Big Rock is a large seeded variety selected for reduced seed dormancy, increased seed weight and increased seedling vigor. It is an excellent food source for pheasants and quail. It has noteworthy winter hardiness for a late season variety. It grows well on diverse soil types and has a wide regional adaptation to the mid-west and northeast regions. Core states for its adaptation are the same as RC Chippewa. However due to its longer growing season it is a better choice than RC Chippewa for more southerly states including Nebraska, Missouri, West Virginia and Virginia. It is well suited for forage, biomass, soil conservation and wildlife habitat applications.